Investigation of Eu-Doped Mesoporous Titania Phosphor with Enhanced Luminescence

A novel mesoporous TiO2 phosphor doped with Eu was synthesized through a facile hydrothermal synthesis method using cetyltrimethylammonium bromide as structure template reagent. The samples were characterized by X-ray diffraction, N-2 adsorption-desorption, scanning electron microscope, high-resolution transmission electron microscopy, ultraviolet visible diffuse reflectance, X-ray photoelectron spectroscopy, and three dimensional Photoluminescence. The X-ray diffraction results demonstrated that the products were anatase type with polycrystalline. N-2 adsorption-desorption analysis showed that the samples were of high ordered double mesoporous structures. Eu-doped mesoporous TiO2 indicated the typical fluorescent spectra of Eu3+ ion occurred: the excited-states at L-5(6) (394 nm), D-5(2) (465 nm) and D-5(1) (535 nm); the main emission peaks at 592 and 617 nm, corresponding with the transitions D-5(0) -> F-7(1) and D-5(0) -> F-7(2), respectively. Meanwhile, the phenomena of Eu3+-doped mesoporous TiO2 phosphor with efficient nonradiative energy transfer from the mesoporous TiO2 host to the activator Eu3+ ions was observed and possible emission mechanism was proposed. High dispersion of Eu in mesoporous TiO2 matrix was responsible for enhanced luminescence.